1. Field of the Invention
The present invention relates to a method of storing data and an apparatus therefor, and more particularly, to a method of and apparatus for storing data in a non-volatile memory.
2. Description of the Related Art
An electrically erasable and programmable read only memory (EEPROM) as a non-volatile memory of a data storage device, such as a smart card, can write and read data by a unit of page at a time. If data has to be written on two pages in the EEPROM, a delay of 3 through 10 ms occurs before data is written on the second page. This time delay exists even when the data is written on the same page while a time gap exceeds 150 microseconds. This time delay causes delay in the smart card response time.
In addition, the life span of the EEPROM is determined based on the number of writes on the EEPROM, and it may be shortened by one spot where data is written more than a hundred thousand times. Therefore, it is desirable that data is written uniformly in the whole EEPROM.
In the conventional art, there have been developed a logging method for transaction processing, a method of synchronizing data in the smart card with backup of the data outside the smart card, and a method of reducing costs in transaction processing. However, implementations of the above methods have not been introduced yet. Moreover, the conventional art has problems in that delay appear when writing data in the EEPROM and the EEPROM has a short life span because data is written too frequently by the unit of log in the EEPROM.
In addition, in the conventional art, any detailed approach for memory management has not been provided, and a spot of the EEPROM, such as a transaction buffer, is too frequently used and the life span of the spot ends, and the EEPROM cannot be used any more although other spots can be used.